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1.
Narrowing down the conditions for extinction of Pavlovian feature-positive discriminations in humans
Priya R. van Vooren Mathijs Franssen Tom Beckers Dirk Hermans Frank Baeyens 《Learning & behavior》2012,40(4):393-404
The aim of this study was to delineate the minimal conditions for extinction of Pavlovian modulation in humans. Previous experiments at our lab showed that, after X ? A+/A?C acquisition training, X?C trials did not extinguish differential X ? A+/A?C responding, while X ? A?C trials did. Additionally, X ? A?C extinction training seemed only to extinguish differential X ? A+/A?C responding, while leaving differential responding on a concurrently trained Y ? B+/B?C discrimination intact. It thus seemed that the X ? A+/A?C discrimination can only be extinguished by X ? A?C extinction trials. (Rescorla, Journal of Experimental Psychology: Animal Behavior Processes 12, 16?C24, 1986), on the other hand, found that the minimal conditions for extinction were broader in pigeons: Namely, he found that an acquired X ? A+/A?C discrimination could be extinguished by presenting the original feature X in combination with a different target (B) that was minimally trained as an exciter. We thus wanted to examine whether this was also the case in humans. We found that nonreinforced X ? B?C presentations did not abolish discriminative X ? A/A responding when target B was a nonreinforced stimulus. Nonreinforced X ? B?C trials did extinguish the X ? A+/A?C discrimination when target B had previously been trained as a target for modulation (X ? B+/B?C or Y ? B+/B?C training) or as a reinforced exciter (B+). Our results thusf parallel and extend those in nonhuman animals (Rescorla, Journal of Experimental Psychology: Animal Behavior Processes 12, 16?C24, 1986). 相似文献
2.
Acquisition, extinction, and transfer of facilitation were explored in a series of experiments with C57BL/6J mice. With a
procedure in which an auditory target was followed by food only in the presence of a visual facilitator, Experiments 1—4 showed
that the facilitator promoted magazine entries to the auditory target. This enhancement effect was eliminated by training
the facilitator as a conditioned inhibitor (Experiments 1 and 3B). Enhancement was also reduced by nonreinforced presentations
of the facilitator in a discrimination procedure (Experiment 1) and by simple nonreinforcement of the facilitator (Experiments
2, 3A, and 4). In contrast to the results obtained with a facilitator, simple nonreinforcement of an inhibitor, a visual cue
that had signaled when an auditory target would not be reinforced, did not reduce its ability to modulate responding to that
target (Experiment 4). However, both the facilitator and the inhibitor were found to transfer their modulatory effects to
other targets (Experiment 4). Finally, mice demonstrated no evidence of differential responding on a biconditional discrimination
procedure in which one auditory target (A1) was reinforced in the presence of one visual stimulus (L1) but not in the presence
of another (L2), and a different auditory target (A2) was reinforced in L2 but not in L1 (Experiment 5). The implications
of these results for analysis of the function of a facilitator are discussed. 相似文献
3.
Thirty rats received 10 sessions of baseline training in which leverpressing was reinforced according to a variable-interval (VI) 60-sec schedule. Twenty-four of the subjects were then assigned to one of four groups that received five sessions of extinction, with groups being differentiated in a 2 by 2 factorial design on the basis of: (1) changes in stimuli accompanying transportation of subjects from home cages to the laboratory and placement in the apparatus, and/or (2) changes in contextual stimuli within the apparatus. During the sixth session of extinction, the transportational and contextual stimuli previously associated with baseline training were reinstated. The remaining six rats experienced changes in both transportational and contextual stimuli but were maintained on the VI 60-sec schedule of reinforcement. Changes in either transportational or contextual stimuli reduced resistance to extinction and spontaneous recovery, and substantial increments in responding occurred upon reinstatement of the transportational and contextual stimuli associated with baseline training. Evidence for summation of the two sources of stimulus change was obtained. Changes in transportational and contextual stimuli produced only a brief disruption in responding when reinforcement of leverpressing was continued. 相似文献
4.
Pigeons received variable-interval (VI) reinforcement for keypecking during randomized presentations of seven line-orientation stimuli forming a continuum ranging from horizontal (0 deg) to vertical (90 deg). Each line presentation lasted for 30 sec and was preceded and followed by 30-sec time-outs. After responding stabilized, only responding in the two extreme stimuli (0 and 90 deg) was reinforced. As discrimination training proceeded, strong behavioral contrast and dimensional contrast effects appeared. However, only marginal local effects (local contrast and local dimensional effects), exerted by one line-orientation component upon a second, appeared, indicating that behavioral and dimensional contrast may be independent of parallel local effects. An attempt was made to apply Blough’s (1975) quantitative model of operant generalization and discrimination to the present discrimination procedure. However, this model did not predict the generalization gradient shape that was experimentally obtained. This experiment also yielded two serendipitous findings: (1) Positive behavioral contrast appeared in an extinction-related stimulus (time-out) when other stimuli were switched from reinforcement to extinction (hitherto, positive behavioral contrast had been observed only in responding to a reinforcementrelated stimulus when other stimuli were switched from reinforcement to extinction), and (2) final responding was higher in the presence of an extinction stimulus that had always been an extinction stimulus than it was in the presence of other extinction stimuli that had previously been paired with VI reinforcement. 相似文献
5.
Three conditioned suppression experiments with rats as subjects investigated the influence of higher order associations in determining the response potential of a target stimulus. In these experiments, a Pavlovian conditioned inhibitor was compounded with the target cue during extinction treatment. In Experiment 1, strong suppression was observed to the target cue that was given extinction treatment in the presence of a conditioned inhibitor, relative to a target that was extinguished with an associatively neutral cue or was extinguished alone, suggestive of enhanced protection from extinction provided by a conditioned inhibitor. This effect was replicated in a sensory preconditioning preparation in Experiment 2; in Experiment 3, in a sensory preconditioning preparation, this protection effect was retroactively attenuated when the conditioned excitor used to train the conditioned inhibitor was extinguished following extinction of the target. This provides evidence that, at least in a sensory preconditioning preparation, stimuli that are only indirectly associated with the target cue can contribute to the response potential of that target. 相似文献
6.
Pigeon subjects received training of a diffuse stimulus as either a conditioned inhibitor or a conditioned facilitator of a keylight signal for food. The ability of these diffuse stimuli to modulate responding was then assessed with two other keylights that were undergoing discrimination reversal. At a point where responding was equivalent for the two targets, the modulators had a greater impact on the target undergoing extinction than on the target undergoing acquisition. These results have implications for the nature of modulation and extinction. 相似文献
7.
Robert A. Rescorla 《Learning & behavior》1997,25(4):485-497
In six experiments, rats received discriminative training in which making a response (R) during a stimulus (S) produced a particular outcome (O). In Experiment 1, that outcome was replaced by a second outcome and responding was tested either immediately or after a delay. More substantial responding was observed with the delayed test. In Experiment 2, a test of transfer to new responses suggested that the growth in performance was not attributable to greater use of particular S-O associations. However, in Experiment 3, the growth in responding was found to be specific to particular S-R combinations. Experiment 4 replicated that specificity and demonstrated the importance of using two different outcomes for obtaining the growth in responding with time. Experiments 5 and 6 repeated these observations for the case of extinction, in which O was replaced by nonreinforcement. These results are interpreted as suggesting that an outcome-independent inhibitory S-R process develops, both with extinction and with the use of a second outcome, but dissipates with time. 相似文献
8.
In Experiment 1, pigeons were trained to peck red or blue keys for food reinforcement at variable intervals, while food was contingent on withholding key pecks in the presence of a vertical line (omission training). When the line was briefly superimposed on red or blue in a compound test, responding was reduced. When the orientation of the line was varied during extinction, generalization gradients were variable but often had most responding at or near vertical. In Experiment 2, pigeons were trained in a discrete trials procedure that made food contingent upon pecking in the presence of triangle, and upon the absence of pecking in the presence of red (omission training). Food was never given on green-key trials (extinction). When red or green backgrounds were presented with the triangle in a compound test, responding was reduced similarly in the presence of both key colors. Subsequent resistance to auto-shaping was also similar for red and green. These data, taken together with reports in the literature, suggest that the inhibitory effects of omission training are quite similar to those of extinction. Thus, the crucial condition for obtaining inhibitory effects is not a negative stimulus-reinforcer correlation, as in extinction, but simply the establishment of low rates of responding to the inhibitory stimulus. 相似文献
9.
Four experiments examined the influence of a stimulus presented after one response in a two-lever choice task. In Experiment 1, food-deprived rats trained on a concurrent variable-interval extinction schedule responded more often on the extinction lever when such responding periodically produced a visual stimulus than when it did not. In Experiments 2 and 3, a similar signal-induced enhancement effect was found even when food was delivered randomly with respect to responding on both levers or when no food was presented. In Experiment 4, a response-contingent visual stimulus elevated responding to the lever on which it was presented, but an auditory cue suppressed responding. These findings indicate that visual stimuli may possess intrinsically reinforcing properties for rats. 相似文献
10.
In three experiments, we assessed the role of signals for changes in the consequences of cues as a potential account of the
renewal effect. Experiment 1 showed recovery of responding following extinction when acquisition, extinction, and test phases
occurred in different contexts. In addition, extinction treatment in multiple contexts attenuated context-induced response
recovery. In Experiment 2, we used presentations of an extraneous stimulus (ES), instead of context shifts, and found that
responding recovered from extinction only when the ES was presented both between acquisition and extinction and between extinction
and test. In Experiment 3, we used a reversal learning design in which, during training, two cues were first paired with different
outcomes, then paired with the alternative outcomes, and finally paired again with the original outcomes. In this experiment,
presentation, just prior to testing, of an ES that had previously been presented between the different phases produced an
expectation of reversal in the meaning of the cues. 相似文献
11.
Pigeons were trained on a two-component multiple schedule in which each separate component consisted of a three-link chain schedule. After initial baseline training, the stimuli correlated with the terminal links of each chain were presented in a successive discrimination, with one stimulus continuing to be associated with reinforcement while responses to the alternative stimulus were extinguished. Subjects were then returned to the original chain schedule, but with extinction in effect in both components of the multiple schedule. In two separate experiments, extinction of initial-link responding was not affected by which terminal link had been extinguished during the separate discrimination training, indicating that devaluation of the terminal link was not transmitted directly to the initial link of the chain. There was also no effect of the devaluation procedure during the first session of testing on responding in the middle link of the chain, but an effect did develop with continued extinction of the entire chain when the terminal components were presented during extinction. When the terminal components were omitted, however, the latter effect did not occur. Also, when the terminal link was omitted, extinction occurred more rapidly in the middle component than in the initial component, indicating a backward pattern of extinction. 相似文献
12.
Rats were trained in a light ON vs light OFF discrimination in operant chambers with food reinforcement. Following acquisition, extinction under conditions of no alternations between S+ and S? and under conditions of numerous alternations between S+ and S? were examined. In Experiment I, extinction in S+ or S? alone produced less responding to S+ and more responding to S? than extinction with regular alternations between S+ and S?. In Experiment II, 9, 39, or 79 alternations in extinction between S+ and S? produced no differences in responding. These results indicate that during extinction of a discrimination there is (a) sharpening of differential performance, (b) a difference between multiple- and single-stimulus procedures, and (c) little effect of different numbers of alternations. 相似文献
13.
The acquisition, maintenance, and extinction of autoshaped responding in pigeons were studied under partial and continuous reinforcement. Five values of probability of reinforcement, ranging from .1 to 1.0, were combined factorially with five values of intertrial interval ranging from 15 to 250 sec for different groups. The number of trials required before autoshaped responding emerged varied inversely with the duration of the intertriai interval and probability of reinforcment, but partial reinforcement did not increase the number of reinforcers before acquisition. During maintained training, partial reinforcement increased the overall rate of responding. A temporal gradient of accelerated responding over the trial duration emerged during maintenance training for partial reinforcement groups, and was evident for all groups in extinction. Partial reinforcement groups responded more than continuous reinforcement groups over an equivalent number of trials in extinction. However, this partial-reinforcment extinction effect disappeared when examined in terms of the omission of “expected” reinforcers. 相似文献
14.
Previous research has demonstrated that discrete cues presented during extinction of a conditioned response (extinction cues) subsequently reduce spontaneous recovery and the renewal effect. In order to assess whether an extinction cue’s effect is due to conditioned inhibition, the effect of pairing an extinction cue with food on the cue’s capacity to modulate spontaneous recovery was investigated in an appetitive conditioning experiment with rats. Conditioned inhibitors paired with the unconditioned stimulus lose their potential to inhibit responding. The food-paired extinction cue did not lose its potential to reduce spontaneous recovery. In fact, it reduced spontaneous recovery more than did an extinction cue that was not paired with food. The results indicate that extinction cues attenuate postextinction recovery of conditioned responding through a mechanism other than conditioned inhibition. The cue’s action appears to be similar to that of serial negative occasion setters. Theories of spontaneous recovery and the relationship of extinction cues to other modulatory stimuli are discussed. 相似文献
15.
Resurgence is the recurrence of a previously reinforced and then extinguished behavior induced by the extinction of another more recently reinforced behavior. Resurgence provides insight into behavioral processes relevant to treatment relapse of a range of problem behaviors. Resurgence is typically studied across three phases: (1) reinforcement of a target response, (2) extinction of the target and concurrent reinforcement of an alternative response, and (3) extinction of the alternative response, resulting in the recurrence of target responding. Because each phase typically occurs successively and spans multiple sessions, extended time frames separate the training and resurgence of target responding. This study assessed resurgence more dynamically and throughout ongoing training in 6 pigeons. Baseline entailed 50-s trials of a free-operant psychophysical procedure, resembling Phases 1 and 2 of typical resurgence procedures. During the first 25 s, we reinforced target (left-key) responding but not alternative (right-key) responding; contingencies reversed during the second 25 s. Target and alternative responding followed the baseline reinforcement contingencies, with alternative responding replacing target responding across the 50 s. We observed resurgence of target responding during signaled and unsignaled probes that extended trial durations an additional 100 s in extinction. Furthermore, resurgence was greater and/or sooner when probes were signaled, suggesting an important role of discriminating transitions to extinction in resurgence. The data were well described by an extension of a stimulus-control model of discrimination that assumes resurgence is the result of generalization of obtained reinforcers across space and time. Therefore, the present findings introduce novel methods and quantitative analyses for assessing behavioral processes underlying resurgence. 相似文献
16.
Rats were used in a lick suppression preparation to assess the contribution of conditioned-stimulus (CS)–context and context–unconditioned-stimulus
(US) associations to experimental extinction. Experiment 1 investigated whether strengthening the CS–acquisition context association enhances extinction by determining whether stronger
extinction is observed when CS-alone trials (i.e., extinction treatment) are administered in the acquisition context (AAC
renewal), relative to a context that is neutral with respect to the US (ABC renewal). Less recovery of responding to the CS
was observed in the former than in the latter case, extending the finding that AAC renewal is weaker than ABC renewal to our
lick suppression preparation. Experiment 2 assessed the contribution of the acquisition context–US association to extinction of a CS by examining the effect of postextinction
exposure to the acquisition context on responding to the extinguished CS. This manipulation enhanced responding to the extinguished
CS in AAC, but not ABC, renewal. Experiment 3 addressed the contribution of the CS–acquisition context association by examining the potential of a neutral stimulus, presented
in compound with the target CS during extinction treatment, to overshadow the CS–acquisition context association. This manipulation
enhanced responding to the extinguished CS in AAC, but not ABC, renewal. The results stress the important role of contextual
association in extinction and renewal. 相似文献
17.
In an experiment with rats, an appetitive conditioning method was used to investigate the generality of the hypothesis that
extinction should arouse attention to contextual cues, resulting in all learning in that context becoming context specific.
Rats received appetitive conditioning with a tone either while extinction of a flasher occurred (Group With Extinction) or
while it did not (Group No Extinction). Half of each group was subsequently tested in extinction in the context in which training
had taken place or in a different context. The results revealed a three-way interaction of extinction and context with trials,
in a direction opposite to the one the hypothesis would suggest. When rats were tested in a different context, there was generally
better responding in Group With Extinction than in Group No Extinction. In the same context, there was generally lower responding
in Group With Extinction than in Group No Extinction. Subsequent testing showed an ABA recovery effect. Results are discussed
in terms of the challenges they pose for the revised retrieval theory presented by Callejas-Aguilera and Rosas (2011). 相似文献
18.
After one-way avoidance training, rats were exposed, during avoidance response prevention, to light (CS-only) presentations or to light-shock (CS-US) pairings. Subgroups were then given 1, 5, or 10 trials during which they could escape immediately (unrestricted) or after 5 sec (restricted) by means of the previously conditioned avoidance response from a simultaneous light-shock compound. All animals were then exposed to avoidance extinction. The number of unrestricted escapes increased responding for CS-only animals, but had no significant effect on the performance of CS-US animals. Nevertheless, resistance to extinction was considerably less for CS-only animals given 10 unrestricted escapes than for CS-US animals given one unrestricted escape. One restricted escape had no more effect than one unrestricted escape for either response-prevention group. However, 5 restricted escapes elevated responding for CS-only animals to the level of CS-US animals. Extinction responding for CS-US animals increased significantly only after 10 restricted escapes. Since CS-only animals showed no further increase, resistance to extinction once more was greater for CS-US animals. These results, together with the very brief unrestricted escape latencies of CS-only animals, support a greater role for Pavlovian extinction than for response competition in the facilitation of avoidance extinction by CS-only response prevention. The fact that 10 restricted escapes were required to elevate resistance to extinction for CS-US animals over that obtained with one unrestricted escape attests to the effectiveness of Pavlovian conditioning during avoidance response prevention in elevating CS aversiveness to a near ceiling level. 相似文献
19.
Todd R. Schachtman Wesley J. Kasprow Robert C. Meyer Mark J. Bourne Julie A. Hart 《Learning & behavior》1992,20(3):207-218
Using a conditioned taste aversion preparation overshadowing of flavor-illness association was produced through the presentation of a second flavor during the interval between the first flavor and illness. The modulatory effects of extinguishing the association between the second (over-shadowing) flavor and illness on conditioned responding to the target flavor was investigated. In Experiment 1, we found that, following one-trial overshadowing, extinction of the overshadowing flavor had no effect on conditioned responding to the target flavor. In Experiment 2, we found a similar absence of an effect of extinction of the overshadowing stimulus in a multitrial over-shadowing paradigm. Experiment 3 confirmed the results of Experiments 1 and 2 using conditioning parameters that were designed to weaken the association between the overshadowed flavor and illness. In Experiments 4 and 5, we used simultaneous presentation of the flavors during conditioning and obtained a weakened aversion to the overshadowed flavor when the overshadowing CS was extinguished. These findings are inconsistent with previous observations in conditioned fear preparations that suggest that extinction of the association between the overshadowing stimulus and the unconditioned stimulus attenuates overshadowing. Possible reasons for the discrepant results are discussed. 相似文献
20.
Four conditioned suppression experiments with rats, using an ABC renewal design, investigated the effects of compounding the target conditioned excitor with additional, nontarget conditioned excitors during extinction. Experiment 1 showed stronger extinction, as evidenced by less renewal, when the target excitor was extinguished in compound with a second excitor, relative to when it was extinguished with associatively neutral stimuli. Critically, this deepened extinction effect was attenuated (i.e., more renewal occurred) when a third excitor was added during extinction training. This novel demonstration contradicts the predictions of associative learning models based on total error reduction, but it is explicable in terms of a counteraction effect within the framework of the extended comparator hypothesis. The attenuated deepened extinction effect was replicated in Experiments 2a and 3, which also showed that pretraining consisting of weakening the association between the two additional excitors (Experiments 2a and 2b) or weakening the association between one of the additional excitors and the unconditioned stimulus (Experiment 3) attenuated the counteraction effect, thereby resulting in a decrease in responding to the target excitor. These results suggest that more than simple total error reduction determines responding after extinction. 相似文献